<h2>DESCRIPTION</h2>

This module makes each cell value a function of the attribute values assigned 
to the vector points or centroids in an area around the cell with a diameter of 
<em>size</em> around it, and stores the new cell values in the <em>output</em>
raster map layer. By default, the module just counts the number of points. The
user can also choose amongst a variety of aggregate statistics using the 
parameter <em>method</em>. These statistics are calculated on the attributes in
the <em>point_column</em>. Using the usual <em>cats</em> and <em>where</em>
parameters the user can chose to take only a subset of the points into account.

<p>
Note that <em>size</em> is defined as the diameter, and so has to be twice the
wanted search radius, and that the module works within the current computational
region which can be adjusted using <a href="g.region.html">g.region</a>. If the
vector map falls completely outside the current region, the module will stop 
with an error.

<h2>EXAMPLE</h2>

Count the number of schools for a given grid (North Carolina sample
dataset):

<div class="code"><pre>
g.region vector=schools_wake res=100 -p -a
v.neighbors input=schools_wake output=schools_wake_3000m method=count size=3000

d.mon wx0
d.rast schools_wake_3000m
d.vect schools_wake
</pre></div>

The result gives for each grid cell the number of points (here: schools)
not farther than 1500 meter away (half of the given <em>size</em> value)
from the respective cell center.

<p>
Calculate the mean capacity of schools for the same grid:

<div class="code"><pre>
v.neighbors input=schools_wake output=schools_capacity point_column=CAPACITYTO \
            method=average size=3000
</pre></div>

<h2>SEE ALSO</h2>

<em>
<a href="r.neighbors.html">r.neighbors</a>, 
<a href="v.vect.stats.html">v.vect.stats</a>
</em>

<h2>AUTHOR</h2>

Radim Blazek, 
Moritz Lennert

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